Variable pitch propeller



Feb. 11, 1936.

F. GoRskl VARIABLE PITCH PROPELLER .Filed sept. 18, 1934 3 Sheets-Sheet 2 x, 1 ai r@ mw v uw NQ, vv R, 9v n 31 n s@ 1 Nb. R Inn. mm m, hw N Nn man vw..

/ .//s/v TUR '/QTTDR/VE vPate-maal' Feb. 11, 1936 PATENT GFFICE VARIABLE FITCH PROPELLEB Frank Gorski, Portland, Oreg., assignor of one- *half to Julia Bucrkowski, Portland, Oreg.

Application September 18, 1934, Serial No. 744,550

s claims. '(ol. 11o-163) This invention relates generally to aviation, adhparticularly to a propeller having a variable p c The main object of this invention is the construction of a variable pitch propeller which will be simple and sturdy in construction and highly eflicient in operation, and which will not easily be rendered inoperative even under severe usage.

The second object is to construct a variable pitch propeller which can be operated while the plane is in flight, and which will remain in any position to which it is set.

The third object is to make it possible for a airplane to have themaximum amount of lifting" action at the desired time without detracting from its speed when altitude is attained.

The fourth object is to provide a variable pitch propeller which will operate through a wide range of settings, including reverse, in order thatthe propeller may contribute to the braking action.

The fifth object is to construct a propeller of the type referred to which can be attached to existing types of motors, or to motors especially designed therefor.

The sixth object is to construct a propeller'of the type described which can be easily lubricated and which is adaptable foruse on three or four bladed propellers as well as those of the two blade type.

parent from the specification following as illus-'- trated in the accompanying drawings, in which:

Fig. 1 is a front elevation of the device.

Fig. 2 is a vsection taken along the'line 2-2 of Fig. 5.

FiFig 3 is a section taken along the line 3-3 in FiFigE; 4 is a section taken along the line 4-4 in Fig. 5 is a longitudinal section through the device.

Fig. 6 is a section taken along the line G -S in Fig. 5.

Fig. 'l is a perspective view ofL the centralsleeve member.

Fig. 8 is a fragmentary view of the propeller mounting showing one of the propellers in end elevation.

Fig. 9 is a perspective view of the operating racks. l

, Fig. 10` is. a. fragmentary transverse section through an alternative vform of a three blade propeller.

55 Fig. 11 is a section taken along the line II--I'I These, and otherobjects, will become more api in Fig. 12 showing an alternative form of the device. Fig. 12 is a section taken along the line I2|2 in Fig. 11.

Similar numbers of reference refer to similar parts throughout the several Views. Referring in detail to the drawings, there is illustrated a cylindrical crank case l5 from which radiate the cylinders I6 of an internal combustion-engine whose crank |1 has its shaft portions |8 and 2| journalingin the bearings I9,

' which are supported in the housings 20 secured to 4each end oi the crank case l5. The forward shaft portion 2| has mounted thereon a 'slotted tubular sleeve 22 which is secured thereto by means of the screws 23.

'I'he sleeve 22 is split along its major axisthc two portions presenting a cylindrical exterior and a cylindrical interior, which isbroken by the ysquare grooves 24 whch extend along the entire length of the interior of the sleeve 22. The grooves 24 form a slide for the racks, Which-will be describedlater.

Each of the portions of the sleeve 22 contains a slot 25, and the edges-26 are cutawaytov-forrn corresponding slots along the lines of union between the portions of the sleeve 22. Surrounding the vsleeve 22 is a flange 21 which serves as a re tainer for a bearing I9.

Projecting radially from yopposite sides of the sleeve .22 and along its line of division, are the bearing arms 28 each of which contains a short shaft 23 constituting the shank of its respective propeller blade 30. 'I'he innermost end of each shaft 23 has secured thereon a pinion 3|. 'I'he pinions 3| are spaced from each other.

'Within the sleeve 22 is placed a-rack slide 32 which-is in the form of an eye, on the inner sides oi.' whose diagonally opposite legs are formed the racks 33. 'I'hese mesh with the pinions 3| and serve to impart rotary motion in opposite direction to the shaft 29 when the rack slide 32 moves within the guiding grooves 24. The web 34 of the rack slide 32 occupies the space between the pinions 3|. The end 35 of the slide 32 is provided with an opening 36.

It is desirable to provide a cap 31 over the end of the sleeve 22. Clamps 38 surround the halves of the sleeves 22 and hold them in position. Suitable grooves 33 receive the clamps V38. Clamps 48 occupy the grooves 4| in the bearingarms 28 and hold'the portions thereof together;

Within the sleeve 22 isl disposed the spherical hub 42 which is attached to the rack slide 32 by means of the bolt 43 which passes through the opening 36. From the hub 42 radiate the spokes 44 which project through theV slots 25 and between the edges 26 and terminate in the track .45, on opposite sides of which are formed the ball races 46 in which are disposed theballs 41.

On the outermost sides of the two sets of balls 41 are the ball race plates 48 which are supported by the finned housings 49'and 5U which, in turn, are joined by means of the bolts 5l and supported by the rods 52 which extend slidably through the brackets 53 and 54 fastened to the l three armed spider 55 which is joined by a connecting rod 56 to the worm wheel 51 by means of the crank pin 58. with a worm 59 o-n the shaft 60. Rotary motion is supplied to the shaft 6B by a hand wheel 6| through the bevel gears 62.

The pitch ofthe worm 59 should be such that it cannot be driven by the wheel 51, and in some instances it will be found desirable to provide a friction brake 63 to prevent the wheel '6I from being moved by vibration, or from any other cause, unless it is manually moved. Obviously, this-friction may be applied at any desired place and may assume the form of a positive lock or jaw clutch, without departing from the spirit of this invention.

The operation of the device is as follows: As-

Vsuming that it is desired to increase the pitch of the blades 31| as when rising from the ground with a heavy load, the operator merely turns the Vwheel 6| in a direction which will cause the wheel 51, through the connecting rod 56, to slide all of the rods 52 and therefore move the housings 49 and 50 and their contained track 45 longitudinally, and consequently move the racks 33 with relation to the sleeve 22, resulting in the rotation of the pinions 3l in CDposite directions thereby varying the pitch of the blades 30. The direction of variance is controlled by the direction the wheel 6l is turned. In certain cases the pitch of the propeller blades 30 may be actually reversed, as when utilizing the propeller as a brake in maneuvering the plane in :making a landing.

It will be noted that the problem of lubricating lthe working parts of this device is quite simple, Aand that the parts which are subjected `to the thrust or pull of the propeller, namely the ball bearings 41 and their associated raceways, are cooled by the radiating ns of the housings 49 and 50.

In the form of the device shown in Figs. 11

12 the large diameter of ball race is Vdispensed 'with and the rack slide 66 has a track 61 of relatively small diameter forming aiiange around one end of vthe slide 66, whereas the tubular shaft 68 extends through the slide 66 and has se- The worm wheel 51'meshes A cured on the end thereof a head 69 which is attached to the hub 1l by means of the screws 1l. A hub cap 12 encloses the end of the hub 1l.

In this form of the device the radiating iins are dispensed with and the rods 52 are attached to the arms 13 whichradiate from the housing 14 in which is contained the races for the ball bearings 15 disposed on each side of the track 61.

I claim:`

1. A variable pitch propeller having in combination a propeller shaft, a tubular sleeve projecting forwardly from said shaft and secured thereto, said sleeve having slots formedtherethrough, a spider having a hub within said sleeve and having spokes thereon projecting through said slots and having a circular track around the ends of said spokes, anti-friction bearings in front of and behind the track on said spider, means for moving said bearings and the intervening spider manually, a plurality oi' pro-I pellerv bladesvprojecting radially from said sleeve andhaving their inner ends extending into same, the inner end of each propeller blade having a pinion secured thereon, a plurality of racks engaging said pinions, and means for connecting said V`racks to said spider whereby the manual movement of said spider will cause said pinions to rotate and the pitches of the propelleis attached thereto to be varied in a manner that the pitches of all of the propellers willbe increased or decreased at the' same time and in a like degree.

2. A device of the class described in which the propeller includes a plurality of blades each of which is adjustably mounted upon the hub in a manner that its pitch can be varied, a rack and pinion movement for adjusting the angularlty of each of the blades, a. spider at one end of the motor having rods connected to the ends thereof adapted to pass around thev exterior of the motor and to be connected to said racks for the purpose of providing a push or pull movement thereto, a crank for actuating said spider, a worm and wheel drive for said crank including means for rotating said worm manually, and means for resisting the rotation of said worm.

3. In a propeller for airplanes, the combination of a radial motor having a tubular propeller shaft and having a plurality of propeller blades projecting radially from said propeller shaft each of which blades is rotatable on its own axis substantially normal to the axis of the propeller shaft, each of said blades having a pinion at its inner end within the propeller shaft. racks within the propeller shaft for rotating said pinions, a spider at the opposite end of the motor having a plurality of rods extending between the ends thereof and the propeller end of the motor, together with means for transferring a push and pull movement on.said rods through said tubular propeller shaft to said racks, and means for actuating said spider in a manner to adjust- `ably x-the position thereof for the' pin'pose of varying the pitch of the various propeller blades.

FRANK AGORSKI. 

